Internal combustion engine



July 5, 1932. L Q FRENCH 1,866,300

INTERNAL COMBUSTION ENGINE Filed. Oct. 25. 1929 7 I I I l N VE N TOR l 25 type wherein the piston traverses the entire the line 45-4: of Fig. 2,

Patented July 5, 1932 I a UNITED STATES PATENT ori ice Louis FRENCH, on MILWAUKEE; wrseoNsin INTERNAL COMBUSTION seems I Application filed ember '26, 1929. Serial No. 4055322.

I The invention relates to internal combusjected to the Washing air current forcedinto tion engines of the liquid fuel inj ection' type. said space along the sides and bottom of said In the injection of liquid fuel into internal chamber and to some extent along'the top,

w combustion engines the directional movethereby producing'a violent,- turbulent ef ment of the jet or jets to secure a thorough feet both during compression and commie: mixing of the fuel Withthe air throughout tionand preventing depositions of the fuel the entire combustion chamber cannot be reon the alls of the chamber; Furthermore; lied upon entirely, but to secure good conr J to more, efficiently direct the gases passing hustion the air in the combustion chamber to and from said chamber fro'in'and to the Y F0 should be utilized to impart directional main part of the cylinder space, inclined so movement of the fuel and fuel mixture to channels in the head communicating tv'ith secure proper distribution of the fuel the main side ports may be employed.- throughout the air and also secure thee'quaL The invention further consists in the sevly important result ofjprev'enting the fuel eral features hereinafter set forth and more depositing upon the Walls of the combus particularly defined by claims at the conclu-j 65 tion chamber. The object of this inventionsion thereof.- o i V is to provide an internal combustion engine In the drawing Fig. 1 is a vertical; section in which the relation of the piston, cylinder al vieiv through an engine embodying the head, combustion chamber and fuel nozzle invention; v 2 are such as to cause an efficient mixing of Fig. 2 is a bottom plan vievv' of the'cylin- 7 the fuel with the air during injection and de'r head; the ensuing combustion process. More par- {Fig 3 is a detail; sectional newt-a ien on ticularly, the invention embodies an internal the line 3- -3 of Fig; 2; V combustion engine of the L-head four cycle Fig. 4 is a detail, sectional view taken on is cylinder space except for a orking clear- Fig; 5 is a detail, side elevation vievv of ance between the head and the top of'the the valve-'0" erating'mechanism; H M piston and a dome-shaped clearance space Referring to the drawing,- the numeralfi or chamber is formed at one side of the cyl: designates the cylinder, 7 the piston working inder restrictedly communicating With the therein, 8 the cylinder head 9 thefuelinj'ec 80 cylinder space, a single valve-controlled port tor, 10 thevalve-control ling the inlet and exg for bothinlet and exhaust of gases opening haust of gases through the single'por't into said clearance space and the fuel noz- 12 the piston slide'valve associated With the zle being located in the top of said domevalve 10 to control the inletpassage 13 and shaped space. The communication between exhaust passage 14. 7 35 the offset chamber and the cylinder space is The cylinder, piston and newness rerestricted in the sense that its area is less lated that when the piston is at the end or than that of the'cylinder bore but it is prefoutward or upstroke the depth 6f thee-pace er'ably at leastequal to that of the entrance 15 between the piston and-head, over the 9b and exit passage to said chamber when the greater portion of its areai is' such aste valve is open and is preferably in the form provide the necessary Working clearance of oppositely disposed ports in the liead'ex therebetvveen and this depth may be deter-j tending from the cylinder space into the mined by the thickn ss of the cylinder headdome-shaped chamber and entering said gasket15. V l v chamber at the sides thereof, said chamber The valve 16) opensinto an offset: or later also projecting at its inner end slightly over ally disposed,- dome-shaped chamber" 16 in a part of the cylinder space. With this concommunication with the cylinder, space 15 struction the fuelis discharged through one through athroat or passage I7 and opposite: or more jets i to the dome-shaped space ly disposed passa'ges18. ThiscliarnberlG is which during this period has its walls sub preferably formed as a recess. in the head,

having a generally elliptical base and conoidally or spherically curved walls, a part 19 of said wall projecting out over the cylinder space and cooperating with the cylinder to form the relatively narrow, centrally disposed throat 17. The passages 18 formed in the head extend from a position adjacent one side of the cylinder space into the chamber 16 at the sides 20 thereof, forming enlargements at these points, and the combined cross-sectional area of these least equal to that of the port opening of the valve 10 so that the flow of gases to or from the cylinder space during suction andexhaust is not restricted, though the total cross-sectional area of the throat 17 and ports 18 is less than that of the cylinder bore and than that of the cross-sectional area of chamber 16 so that communication between the cylinder space and chamber 16 is therefore restricted. The head may also be recessed to provide the slightly upwardly inclined channels or passages 21, extending from the axis of the cylinder to the ports 18, to more readily direct the gases passing to and from the chamber 16 from and to the main part of the cylinder space.

The fuel injector 9 is mounted in the head at the top of the dome 16 and may be of any suitable construction, but is preferably an injector having a single jet of wide spraying angle directed generally downwardly or having several radially disposed jets directing the sprays downwardly and at an incline as denoted by the arrows in Fig. 1.

The valves 10 and 12 are not new per se but the association of the single valve '10 with the combustion chamber above described is novel and enables me to produce an L-head engine in which but a single opening into the combustion chamber is necessary, thereby permitting the fuel nozzle to be located in the best position for efficient fuel distribution and allowing the use'of compression pressures suitable for autoignition either when starting from cold or after heating, and providing a relatively high combustion chamber to prevent the fuel'coming into contact with the walls of said chamber. 7

As shown, the valve 10 is a simple poppet valve, normally seated by a spring 22 inter'- posed between the cap 23 and a disk 24 operatively connected to the stem by a pin 25 extending therethrough. The piston valve 12 has atubular stem 26 in which the stem of the valve 10 is guided and which itself is guidedin a borein the cap 23. This valve is normally held in one of its positions by a spring 27 interposed between the cap 23 and disk 28 secured in any suitable manner to its stern, as by a collar 29 having threaded engagement with'said stem. The pin 25 works in a slot 30 in the stem 26 so that the valve may be moved independently. Any suitable valve mechanism may be used foroperating passagesis preferably at the valves to open the valve 10 during the exhaust and suction strokes of the engine and move the valve 11 to uncover the exhaust port 14 during the exhaust stroke while closing the inlet port 13 and uncovering the inlet port during the suction stroke while closing the exhaust port. By way of illustration in Fig. 5 I have shown, somewhat diagrammatically, a mechanism for this purpose including a tappet 31 operated by a suitable cam 32 on the cam shaft 33 of the engine to control the valve 10 and a tappet 34 operated by a cam 35 on said shaft and acting on a tappet lever 36 suitably pivoted on the engine rame and having forked ends 37 straddling the stem of the valve 10 and engaging the collar 29. Either one of the ports controlled by the valve 12 may be the inlet and the other the outlet but it is preferred to use the lower port as an inlet port so that the entering air may act to cool the piston valve.

The bottom of the chamber 16 is shown slightly inclined and the port 11 inclining outwardly. This is not essential but it facilitates the formation of the jacket space around the valve mechanism and permits a reduction in the length of the chamber 16 that might otherwise be employed.

With the construction above described, during the upwardmovement of the piston 7 on the exhaust stroke the valve 10 is opening and the valve 12 is then in a position to allow the products of combustion to pass out through the exhaust port 14. As the piston starts over dead center the valve 12 shifts to uncover the inlet port 13 and cover the exhaust port and the valve 10 still being open the cylinder receives its charge of. air during the ensuing downstroke of the piston. As the piston starts on its compression or next upstroke the valve 10 closes and the piston valve is moved down to uncover the exhaust port and cover the inlet port. As compression proceeds the gases in the cylinder space are forced through the throat 17 and passages 18 into the chamber 16 and set up a pronounced turbulence therein. Near the end of the compression stroke the fuel is sprayed into the chamber 16 under the requisite pressure and at this time the piston 7 is close to the head and in addition to the washing effect of the gas streams forced into the chamber through the passages 18 and 17 a thin stream of gas is forced across the bottom of the chamber 16. At the end of compression with the piston on upper dead center the greater portion of the compressed gases are in the chamber 16 and being mixed with the fuel and combustion is starting.

During the next down stroke combustion proceeds and the expanding gases issue from the chamber 16 into the cylinder space and drive the piston downwardly, after which the cycle is repeated. The injection ofthefuel is preferably regulated so that combustion is partly at constant volume and the so-called mixed cycle that partly at constant pressure though for some purposes the combustion may be at predominately constant volume.

Ignition of the charge may be solely by the heat of compression or assisted on starting by a hot wire plug 38 or other suitable device, depending upon the compression pressures used.

I desire it to be understood that this invention is not to be limited to any particular form or arrangement of parts except insofar as such limitations are included in the claims.

What I claim as my invention is:

1. In an L-head internal combustion engine, the combination of a cylinder, a piston working in said cylinder, a domessha'ped combustion chamber offset from and in restricted communication with the end of the cylinder, said combustion chamber forming substantially the entire clearance space when the piston is at the end of its compression stroke, a single inlet and exhaust port communicating with said combustionchamber, a valve controlling said port, and a fuel in jector mounted in. the upper part of said dome-shaped chamber and discharging toward the lower portion thereof as the piston completes its compression stroke.

2. In an L-head internal combustion engine, the combination of a cylinder, a piston working in said cylinder, a dome-shaped combustion chamber offset and in restricted communication with the end of the cylinder but overlying a relatively narrow sector thereof, said substantially the entire clearance space when the piston is at the end of its compression stroke, a single inlet and exhaust port communicating with said combustion chamber, a valve controlling said port, and a fuel intakes place on jector mounted substantially centrally in the top of said chamber and discharging toward the lower portion thereof as the piston completes its compression stroke.

3. In an L-head internal combustion engine, the combination of a cylinder, a piston working in said cylinder, a dome-shaped combustion chamber offset from the end of the cylinder and having laterally disposed passages extending into the end of the cylinder and providing a restricted communication between said chamber and the end of the cylinder, said combustion chamber forming substantially the entire clearance space when the piston is at the end of its compression stroke, a single inlet and exhaust port communicating with said combustion chamber, a valve controlling said port, and a fuel injector mounted in the top of said chamber and discharging toward the lower portion thereof.

4:. In an gine, the combination of a cylinder, a piston and having laterally combustion chamber forming L-head internal combustion enchamber forming substantially the entire clearance space when the piston is at the end of its compression stroke, a single inlet and exhaust port communicating with said combustion chamber, a valve controlling sai port, the combined area of the passages to the end of the cylinder being at least equal to that of said single passage when said valve is fully open, and a fuel injector mounted in the top of said chamber and discharging toward the lower portion thereof.

5. In an L-head internal combustion engine, the combination of a cylinder, a piston working in said cylinder, a dome-shaped combustion chamber having spheroidally curved walls in restricted communication with the end of the cylinder but overlying a relatively narrow sector thereof, said combustion chamber forming substantially the entire clearance space when the piston is at the end of its compression stroke, a single inlet and exhaust port communicating with said combustion chamber, a valve controlling said port, and a'fuel injector mounted in the top of said chamber and discharging toward the lower portion thereof.

6. In an L-head internal combustion engine, the combination of a cylinder, a piston working in said cylinder, a dome-shaped chamber offset from the end of the cylinder disposed passages extending into the end of the cylinder and providing a restricted communication between said chamber and the end of the cylinder, there being grooves of reduced cross-section in the head leading from said laterally disposed passages out over the main part of the end of the cylinder, said combustion chamber forming substantially the entire clearance space when the piston is at the end of its compression stroke, a single inlet and exhaust port communicating with'said chamber, a valve controlling said port, and a fuel injector mounted in the upper part'of said chamber and discharging toward the lower portion thereof. 7

In testimony whereof, I affix my signature.

LOUIS o. FRENCH. 

